Eduard Grüneisen (26.05.1877-5.04.1949) was a German physicist. He was born in Giebichenstein. He studied at the universities of Halle and Berlin. Doctor of Philosophy (1900). He began working as an assistant to F. Kohlrausch at the Physico-Technical Institute (Berlin — Charlottenburg) (from 1911 as head of a laboratory and from 1919 of a division). From 1927 he was professor at the University of Marburg and director of the university's Institute of Physics.
His research concerned solid-state physics, magnetism and low-temperature physics. In 1908 he established that the ratio of the coefficient of thermal expansion of a metal to its specific heat capacity is independent of temperature (Grüneisen's law), and in 1911 he obtained a formula relating the frequency of the vibrations of the atoms of a crystal lattice to the elastic constants of the crystal (the Grüneisen formula). He gave a formula describing the dependence of the ideal part of the electrical resistivity of metals on absolute temperature (the Bloch — Grüneisen formula). He was one of the founders of the theory of solids, and developed (1919) a general theory of the crystalline state.